(*) Dept. of Geosciences, University of Massachusetts, Amherst, MA 01003-5820, U.S.A.
(%) Dept. of Biology, University of Massachusetts, Amherst, MA 01003, USA.
(#) Present Address: Department of Geology, University of Toronto, 22 Russell St., Toronto, Ontario, M5S 3B1, Canada.
Abstract
Diatom preserved in the sediments of Lake C2 (82.50 N, 76.00 W), a high arctic meromictic lake, track changes in the lake's salinity which have occurred as the basin was isolated from the sea. An assemblage dominated by marine taxa, such as Chaetoceros species, Nitzschia cylindrus and Diploneis spp., was replaced by Cyclotella kuetzingiana var. planetophora dominated freshwater flora. A brief brackish period separates the two assemblages. Relatively little floristic change occurred within either the marine or the freshwater periods, indicating rather stable environmental conditions, except that rheophilous diatoms fluctuated in relative abundance during the lacustrine phase, perhaps tracking past changes in discharge from inflowing streams. These may reflect periods of warmer, wetter environmental conditions.